West Ham could be without influential midfielder Mohamed Diame for up to three months after he tore his hamstring during the Hammers' defeat to Liverpool.

Three former West Ham players - Glen Johnson, Joe Cole and Jonjo Shelvey - all helped sink their former club as Liverpool moved into the top half of the Premier League for the first time this season with a 3-2 victory at Upton Park.

Diame has been a key figure for West Ham this season and after losing striker Andy Carroll to injury last week, manager Sam Allardyce was left ruing his bad luck.

"Not good - it does not take a medical expert to know it is a serious hamstring tear when he falls and stopped the way he did," Allardyce said. "I would expect, in medical terms, for it to be a Grade 3 [injury] and that could be anything up to eight, ten or 12 weeks."

The Hammers, who went behind to Johnson's early strike, recovered well to lead 2-1 after Mark Noble's penalty and an own goal by Steven Gerrard, but appeared to lose their way after Diame was stretchered off in the second half.